I have read through many articles, papers, etc. about the pros and 
     cons
     of using Nitrogen in the reflow process. It appears that oxygen levels 
     of 1000 ppm or less is recommended with Nitrogen use. The benefits 
     being less solder balls, better alignment, and better wetting. The 
     price of the Nitrogen consumption is the concern.
     
     Does anyone have supporting information not to use Nitrogen as a cost 
     saving/reduction without significantly affecting reliability?